Golf balls can generally be divided into two classes: solid and wound. Solid golf balls include one-piece, two-piece (i.e., solid core and a cover), and multi-layer (i.e., solid core of one or more layers and/or a cover of one or more layers) golf balls. Wound golf balls typically include a solid, hollow, or fluid-filled center, surrounded by tensioned elastomeric material, and a cover. Solid balls have traditionally been considered longer and more durable than wound balls, but also lack the particular “feel” that is provided by the wound construction and typically preferred by accomplished golfers.
By altering ball construction and composition, however, manufacturers can vary a wide range of playing characteristics, such as resilience, durability, spin, and “feel,” each of which can be optimized for various playing abilities, allowing solid golf balls to provide feel characteristics more like their wound predecessors. The golf ball components, in particular, that many manufacturers continually look to improve are the center or core, intermediate layers, if present, and covers.
The core is the “engine” of the golf ball when hit with a club head. Generally, golf ball cores and/or centers are constructed with a polybutadiene-based polymer composition. Compositions of this type are constantly being altered in an effort to provide a targeted or desired coefficient of restitution (“COR”) while at the same time resulting in a lower compression which, in turn, can lower the golf ball spin rate, provide better “feel,” or both. This is a difficult task, however, given the physical limitations of currently-available polymers. As such, there remains a need for novel and improved golf ball core compositions.
Manufacturers also address the properties and construction of golf ball intermediate and cover layers. These layers have conventionally been formed of ionomer materials and ionomer blends of varying hardness and flexural moduli. This hardness range is still limited and even the softest blends suffer from a “plastic” feel according to some golfers. Recently, however, polyurethane-based materials have been employed in golf ball layers and, in particular, outer cover layers, due to their softer “feel” characteristics without loss in resiliency and/or durability.
There remains a need, however, for improved golf ball center, core, layer, cover, and coating materials and/or blends having further reduced or modified hardness and modulus while maintaining acceptable resilience and superior abrasion resistance and feel. The present invention is directed to golf balls having components formed of novel hybrid materials, such as modified glass ionomers, ormocers, and other inorganic-organic materials.
Ormocers, for example, are a relatively new class of composite materials formed of ceramic and polymer networks that combine and interpenetrate with one another. Ormocers may be generally classified as one, either organic- or inorganic-doped systems typically based on one major phase containing a second one in a relatively low amount; and two, either organic- or inorganic-doped systems in which the fraction of each component in the system is of the same order of magnitude. These and other novel hybrid materials described herein are investigated for use in a variety of golf ball components that include, but are not limited to, golf ball centers, cores, layers, covers, and coating materials and/or blends, continuous or non-continuous layers, thick of thin films, fillers, fibers, flakes, windings, adhesives, coupling agents, compatibilizers, composites, reinforcements, and inks.